Congress is facing a fork in the road in the Internal Revenue Service's tea party-harassment scandal.

It may have to take both.

But, first, Republicans in the House must come to terms with a decision they really — really — do not wish to make.

They will have to offer immunity from prosecution to Lois Lerner, the IRS retiree who has refused to testify and whose emails so amazingly disappeared when her computer hard drive crashed.

And if they fail to get to the bottom of the IRS shenanigans through Lerner? Well, there is a Plan B. They can appoint a special prosecutor — and accept all the expense and power-wielding baggage that comes with such an appointment.

Following the contempt-dripping theatrics of IRS Commissioner John Koskinen, the GOP lawmakers have no choice but to take one or both of those dramatic steps. ... Lerner, of course, has been no more willing to get to the bottom of events than Koskinen. Or, for that matter, the Justice Department, whose own half-hearted investigation is languishing ... somewhere. Or, for that matter, the White House, which simply could order agencies that may have communicated with Lerner, et al, to cooperate.

Their determined resistance is beginning to tell its own suspicious story. If Lerner dodges Congress again, despite immunity, there is always the special prosecutor route. It may be the only way to make sure this episode is never repeated, by administrations of either party.

On Tuesday, U.S. District Judge Reggie Walton issued an order to hear oral arguments from lawyers representing the Internal Revenue Service and the conservative nonprofit True the Vote. True the Vote is one of the conservative groups claiming IRS improperly targeted its application for nonprofit status based on the group’s political and philosophical affiliation. True the Vote filed a motion for a preliminary injunction and expedited discovery on Monday, calling for an independent forensics examination of any IRS hard drives, servers, or other computer hardware involved in the government agency’s possible targeting of conservative nonprofits’ applications for tax-exempt status. It wants an outside computer expert to try to ascertain how and when any electronic evidence, such as former IRS Commissioner Lois Lerner’s emails, may have been lost. Also, it would be great if the government didn’t spoliate — I mean “recycle” — any more evidence….

In its motion, True the Vote argues that the law obligated the IRS to preserve potentially relevant evidence, including electronically stored information. The IRS knew that the hard drives and emails of Lerner and other officials were of significant legal interest. By the time the agency supposedly began disposing of Lois Lerner’s computer hardware, Congress was publicly investigating the IRS scandal. Pro-Israel group Z Street, Inc. filed suit in August 2010, alleging similar improper targeting as True the Vote claims. In September 2013, True the Vote itself sent a litigation hold letter to counsel for the IRS officials, including Lerner, who the group believed were involved in IRS wrongdoing. The government clearly had notice that the computer equipment and information should be preserved as potential evidence.

If the account alleged in True the Vote’s motion is accurate, opposing counsel was none too cooperative. Despite earlier attempts to confer with IRS counsel, attorneys for True the Vote did not learn of the missing emails of Lois Lerner and other IRS officials until Friday, June 13, 2014, when news reports publicized the loss. On that day, IRS finally informed Congressional investigators that the agency could not recover two years’ worth of Lerner’s emails. Apparently, Lerner’s hard drive crashed in 2011, its data was unrecoverable, and the government had no available back-ups.

Talk about bad luck — finding out on Friday the 13th that two years’ worth of emails spanning the time period when you believe the federal government committed illegal acts have been “lost.”

Of course, it is hard to believe in bad luck when federal-government malfeasance is involved. Did IRS officials violate True the Vote’s constitutional rights by improperly singling out their application for tax-exempt status as the conservative group claims? Was this politically motivated targeting the result of overzealous lower-level employees? Did members of the Obama administration orchestrate this campaign to punish the administration’s political enemies? We don’t know. That’s the kicker about the spoliation of evidence.

IRS explanations of how Lerner’s emails during the crucial time period were lost have not inspired much confidence, under the circumstances. Perhaps the only reason to believe that the IRS and Obama administration are telling the truth about the lost evidence and the IRS scandal is that their explanations look so extraordinarily — almost laughably — suspicious that someone would have to have “courage” the size of the U.S. Treasury to claim such things with a straight face.